1. Field of the Invention
The present invention relates to a terminal box for solar cell module.
2. Description of the Related Art
A solar cell panel constituting a solar power generation system is composed of a plurality of solar cell modules, and electrodes of the respective solar cell modules are connected in series or in parallel via terminal boxes.
A terminal box disclosed in Japanese Examined Patent Application Publication No. 3498945 includes a housing in the form of a shallow box, a pair of terminal plates laid on a bottom part in the housing and electrically connected to a solar cell module, and a bypass diode (rectifying element) at the time of a reverse load which diode is bridged between the both terminal plates. Leads of electrode portions of the solar cell module are connected by soldering to one end portions of the respective terminal plates through openings formed in the housing, and end portions of cables drawn out from the housing are connected by crimping to the other end portions of the terminal plates. Silicon resin is poured into the interior of the housing with the leads of the solar cell module and the end portions of the cables respectively connected to the both end portions of the terminal plates and the bottom surface of the housing bonded to the underside (underside when used) of the solar cell module, whereby connected parts are sealed around by the resin. Further, the housing is closed by a lid after the silicon resin is poured.
Since a diode reaches a very high temperature in exhibiting its function, it is required to release heat generated by the diode to the outside. However, in the above construction, a thick layer of the silicon resin having a low thermal conductivity is included in the housing, wherefore it is difficult to release the heat generated by the diode to the atmosphere via the silicon resin in the housing. Thus, the heat generated by the diode is mostly released to the solar cell module via the bottom part of the housing, with the result that the diode may be damaged without the heat being sufficiently released.
The present invention was developed in view of the above problems and an object thereof is to provide a terminal box for solar cell module having a good heat radiation property.